CVE-2020-14150

GNU Bison before 3.5.4 allows attackers to cause a denial of service (application crash).

5.5 MediumFix available

GNU Bison before 3.5.4 allows attackers to cause a denial of service (application crash). NOTE: there is a risk only if Bison is used with untrusted input, and an observed bug happens to cause unsafe behavior with a specific compiler/architecture. The bug reports were intended to show that a crash may occur in Bison itself, not that a crash may occur in code that is generated by Bison.

Attack profile

How easy it is to exploit

Attack vector: Local
Complexity: Low
Privileges needed: Low
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

0.39%Down 0.4 points since Apr 14, 2021

What each source reports

NVD Score used 5.5

Record: CVE-2020-14150
CVSS 3.1: 5.5 MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS 2.0: 2.1 LowAV:L/AC:L/Au:N/C:N/I:N/A:P
Updated: 2026-11-02

CVE List No score

Record: CVE-2020-14150
Updated: 2026-11-02

EUVDEUVD-2020-6307 No score

Record: EUVD-2020-6307
Updated: 2026-11-03

GitHub AdvisoriesGHSA-wqmg-pp5q-5hqr 5.5

GNU Bison before 3.5.4 allows attackers to cause a denial of service (application crash).

GNU Bison before 3.5.4 allows attackers to cause a denial of service (application crash).

Record: GHSA-wqmg-pp5q-5hqr
CVSS 3.1: 5.5 MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSV 5.5

Record: CVE-2020-14150
CVSS 3.1: 5.5 MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVDEBIAN-CVE-2020-14150 5.5

Record: DEBIAN-CVE-2020-14150
CVSS 3.1: 5.5 MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVJLSEC-2026-117 5.5

Record: JLSEC-2026-117
CVSS 3.1: 5.5 MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS 2.0: 2.1 LowAV:L/AC:L/Au:N/C:N/I:N/A:P
Updated: 2026-11-02

OSVUBUNTU-CVE-2020-14150 5.5

Record: UBUNTU-CVE-2020-14150
CVSS 3.1: 5.5 MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVMGASA-2021-0023 No score

Updated bison packages fix a security vulnerability

It was discovered that GNU Bison before 3.5.4 allows attackers to cause a denial of service (application crash) (CVE-2020-14150).

Record: MGASA-2021-0023
Updated: 2026-11-02

Affected products

gnu bison

Affected packages

Affected packages
Package	Affected	Fixed
`bison` Debian:12	before 2:3.6.1+dfsg-1	2:3.6.1+dfsg-1
`bison` Debian:13	before 2:3.6.1+dfsg-1	2:3.6.1+dfsg-1
`bison` Debian:14	before 2:3.6.1+dfsg-1	2:3.6.1+dfsg-1
`Bison_jll` Julia	before 3.8.2+0	3.8.2+0
`bison` Mageia:7	before 3.5.4-1.mga7	3.5.4-1.mga7
`bison` Ubuntu:16.04:LTS	All versions, plus listed versions 2:3.0.2.dfsg-22:3.0.4.dfsg-1	None known
`bison` Ubuntu:18.04:LTS	All versions, plus listed versions 2:3.0.4.dfsg-1build1	None known
`bison` Ubuntu:20.04:LTS	All versions, plus listed versions 2:3.4.1+dfsg-42:3.4.2+dfsg-12:3.5.1+dfsg-1	None known

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2020-14150 is a medium vulnerability (CVSS 5.5) in Gnu Bison, published June 15, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.39%, the 32nd percentile. Fixed in bison 2:3.6.1+dfsg-1.